Rotary kiln.



MTBNTED MAY o. ELLIS.l

ROTARY KILN.-

APPLIUATION PXLED 0UT.31.1006

@witnesses dirigible flame of high heat head of the kiln and Fig.

cantaron ELLIS, or WHITE PLAINS, NEW Yoan.

ROTARY KILN.

No. eet/,ela

Specification of Letters Patent.

Patented may 12, isos.

Application filed' October 31,1205. Serial No. 235,265.

To all whom it may concern:

Be it known that i, CARLETON ELLIS, a citizen ,of the United States, anda resident of White Plains, in the county of 'Vestchester and State orNew York, have invented certain new and useful Imi rovements in RotaryKilns, of which the' following is a specification.

This invention relates to gas burners for the combos tion ol'` producergas in its application as a fuel for the burning of cement. The ordinaryforms of ports heretofore tried for this purpose have not provensatisfactory owing to the inability 'to properly direct the llame andcontrol the rate of combustion. Producer gas being an exceedingly diluteform of fuel, great volumes of it are required to heat a rotary cementkiln with correspondingly large-orificed burners and for this reason,vand for the reason that if used as hot as it leaves the producer highpressure purnpi machinery is almost recluded., .it is very illicult tocause it to urn within the lrilnin a positive, well-developed flame. f

For the burning of cement a very rapid rate of combustion is necessaryand as a high temperature is required in the lowerpart of the kiln wherethe clinlrering operation is performed ordinary methods and gas arepoorly suited for application to the burning of producer gasfor themanufacture of cement, in as much as the rapid mixture and developmentof high temperatures is not easily secured.

This invention has lor its object an apparw.

tus so constructed that a positive, uni erm, intensity may be Securedwith producergas.without difficulty.

` In the accompanyingdiagrammatic drawings Figure 1 represents a sectionof the apparatus or burner. Fig. 2 is an end elevation showing 'theconnections with the hood or 3 represents a longitudinal view of theburner and kiln. Fig. 4 is a view similar to Fig. 1, illustrating analternative form of draft nozzle. Fig. 5 shows, on a larger scale, atransverse section of, the draft nozzle of Fig. 1. Fig. 6 shows atransverse section of an alternative l'orm of gas port. And Fig. 7 is oview similar to Figui?, illustrating the setting of the air and gasinlets to one side of the axis, to causo the llame to iznpinge up on thecement material clinging to the tip-turning side oi the kiln.

the employment of' of mixing air `drawing air through the pipe 1 Likereference characters designate like parts in the several figures;

Referring to Fig. 1, 1 is a hood or header closing the end of the kiln2.

3 isthe gas port supplied with gas from the underground conduit 4 shownin .Fig 3.

5 is the housing or dust chamber inclosing the upper end of lthc kiln,on which housing is situated the stack 6. In thc gas port 3 is situatedthe air supply pipe 7 through which preferably low pressure air as froma centrifugal blower is supplied.

81s a pipe or jet through which compressed au may 'e admitted. lt 1sprcl'orablyplaced inside the pipe r and is preferably given a bend ofsuch direction, at a point such as Si", s'o that the jet of air lormcdissues in an oblique non-radial direction with respect to the Iaxis ofpipe 7, so that the blast of air in the pipe 7 is given a rotary motionas it discharges into the gas port 3. 'The passage 7 as shown is notintroduced so lar into the gas port as to project into the kiln but isprefer-` ablysituated back in the port at a short distance from theoutlet oi" the latter.

9 is a stove for'preheating the air employed and 10 is a Jfan supplyingthe necessary air required for combustion, except suoli as is admittedthrough the jet 8 or enters through the clinker discharge passages or byinfiltration.

The operation of my apparatus is as follows IAssuming that the kiln is4started from the cold condition, a. wood iirc is built in its lowerend, and when it is woll heated gas is admitted through thc port Si Thefan 10 is then put in motion, forcing a blast of air throu through t 1epipe 7. The air and gas ignite at the mouth of the gas port and burnwith a flame of high heat intensity. The compressed air is admitted'insuitable amount through jet 8 to secure the necessary adminture'of thegas and to assist in directing the llame to the point wherethe heat mustbe generated most rapidly. Tho pipes 7 and 8 are hinged,. at 7al and 8arespectively, as shown'in Fica l, so that their ond portions, beingdirigib e, may be moved or vdirected to Agive thc llame its mosteffective location.

The compressedv air jet acts inductively,

'7 and thereby assisting thc fan 10 whic 1 may be run at-a lesser'presser than would bo otherwise required. The fan 10 may .bc employed toh the stove 9 and'discharging it 'forms of preheating stoves at theopposite end or pro ucts of combustion or air in predetermined amountaccording to the quality of the llame desired. ln Fig. S l show a valvedpipe l1 connecting thel intake ofthe fan to stack 6, for mixing productsof combustion With the entering air current. i

sup ly a blast of pure air or of one containing l l l Products of lcombustion added in small quantity to the i air supply reduce thetendency to the forniation of rings in `the kiln..

ln place of the inductive iet S l have used a specially constructedforni of jet blower, shown in Fig. Il, constricted around the jet, Whichexerts a greater inductive action than the jet in -a tube of even boreis capable of eecting. The eilicient induction so produced is desirable,I have found, in certain owing to the loss in velocity of the air blastin traveling through the tortuous passages of the pren heating stove. lhave found that with apparatus somewhat| similar to that hereillustrated that the fan l0 when operatedy to give a pressure of 7i12/of Water at its outlet affords f the stove a pressure of only l i/e,so great is the friction loss of the air in traversing the stove. Bymeans o the inductive `iet the pressure in increased at the kiln and thevelocity required is more easily secured. l have found that highvelocity of delivery of air into the kiln is very desirable and in oneinstance l found that i?" to 18 of pressure as shown by the Water gagein conjunction with auxiliary supply of compressed air afforded betterresuits than Where pressures of 2 and 3 were employed.`

As indicated in the drawing, the gas port is preferably circular in itscross section atl its discharge end, but l have found other forms orshapes for the discharge opening to be also efficient; as for instancethe square port with arched roof, shown in Fig. 6.' The diameter of thepipe 7 must not be so great as to block the passage of gas in the port3, neither should the discharge end of the pipe be laced so far backinthe port 3 as to exert a c oking action by virtue of combustionoccurring in the port itself to an appreciable extent. The diameter ofthe pipe 7 lwill also vary With thel blast pressure em loyed. With a gasport AZ3 in diameter have found an 8 pipe to Work 'Well for the airsupply when the air Was preheated to 3500 and Was introduced at apressure of about 3 by the Water gage. In another instance with a port2G in diameter for the gas and with an air blast pipe of only e but witha fan pressure of 17 I secured a concentrated ame which gave thelocalized heat especially suited for the production of clinker.

The high and low pressure air used with this apparatus may be preheatedin any suitable manner. To this end l have shown a separately firedstove 9 for heating the loaT l essere roni the generator to the kiln insuch a Way that the radiation loss is kept as low as pos- Y S ible.

The gas and air ports are preferably lo cal-.od as shown in thedravgi-rigl'th'at is to say so directed as to produce a iioW of gas intothe kiln near its axis. l have also found it possible to set theporteither to the lel't or right of the center, depending upon thedirection of rotation of the kiln, so that the llame instead of burningaxially in the kiln will inipinge upon the material, thereby geireratingthe heat at the point of its absorption. T his is illustrated in Fig. 7,in which figure the gas and air inlets are shown to the leit of the axisof the kiln, rotation being up Ward on such left-hand side, as indicatedby the arrow, so that-the flame will impinge on the cement materialwhich., by clinging to the side of the kiln, is carried upward a shortdistance on the 11p-turning side of the kiln. rihis is speciallydesirable when the air em I loyed has not been preheated.

The combination with a horiaontal inclined kiln, of a source of heatinggis, and a gas burner therefor comprising a gas port arranged to directgas into said kiln and having Within it low pressure and high pressureair passages arranged one Within the other.

2. rlhe combination with a horizontal inclined kiln, of a source ofheating gas and a gas burner therefor comprising a gas port arranged todirect gas 'into said kiln and having Within it low pressure and highpressure air passages arranged one Within the other, and means forheating the low ressure air.

3. The combination Witi ya horizontal inclined kiln, of a source vofheating gas and a gas biirner therefor comprising a gas ort arranged todirect gas into said kiln anc having Within'it low lpressure and highpressure air passages arranged one within the other, and means for.heating both the loW pressure and the high pressure air.

fi. The combination with a horizontal inclined kiln, of a source ofheating gas and a gas burner therefor comprising a gas port arranged todirect gas into said kiln and having Within it low pressure and highpressure air aesages arranged one Within the other, 'said burnercomprising means for directing the Haine at will.

5. rilhe combination with a` horizontal in` clined kiln, of a source ofheating gas and a gas burner therefor comprising a gas port ar ranged todirect gas into said kiln and having Within it low pressure and highpressure air passages arranged one within the other, and comprisingdirigible end sections.

6. The combination With a horizontal in clined kiln, of a source ofheating gas and a lee gas burner therefor comprising a gas ranged todirect gas into said kiln a having wit in it low pressure and highpressure air passages arranged Ione within the other, said urnercomprising means for imparting ro tary motion to the low pressure airjet.

The combination with a horizontal inelined kiln, of a source of heatinggas and a gas burner therefor comprising a gas ort arran ed to directgas into said kiln an "having Wit in it iow pressure and high pressureair assages arranged one within the other, said igh-pressure passageprovided with means for imparting rotary motion to the low pressure airjet.

8. The combination with a horizontal inclined kiln, of a source ofheating gas and a ortl ar- I gas burner therefor comprising a gas portarranged to direct gas into said kiln and having within it low pressureand high pressure air passages, the high the low pressure passage andhaving an end portion projecting angularly and nonradially with respectto the axis of said low pressure passage, whereby rotation of the lowpressure air jet is roduced.

Signed at New ork, in the county of New York, and State of New York,this 25th day of October, A. D. 1905.

CARLETON ELLIS.

Witnesses: r-

FLETCHER P. SGOFIELD, FRED A. CHAMBERLAIN.

pressure passage within-

